build(deps): bump actions/checkout from 4 to 5

Bumps [actions/checkout](https://github.com/actions/checkout) from 4 to 5.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v4...v5)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '5'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/publish-to-pypi.yml

@@ -14,7 +14,7 @@ jobs:
     if: github.repository == 'django-components/djc-ext-pydantic'
     steps:
       - name: Checkout the repo
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: Setup python
         uses: actions/setup-python@v5

.github/workflows/tests.yml

@@ -16,7 +16,7 @@ jobs:
         python-version: ['3.8', '3.9', '3.10', '3.11', '3.12', '3.13']
 
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v5
 
     - name: Set up Python ${{ matrix.python-version }}
       uses: actions/setup-python@v5